Returning server IP address in Response object

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While working with httplib2, I realized that when a Http `request' is done 
starting from a URL there is no way for telling which server IP address it 
connected to. This feature could be really useful for a project I'm currently 
working on based on httplib2. Moreover, taking a look at the Http class code, I 
realized that it should be not so hard to include such information in the 
Response object returned by the `request' method. 

Thanks,
Angelo

Original issue reported on code.google.com by angelo.d...@gmail.com on 3 Jul 2012 at 9:07